We gel isolated, digested and then cloned the assembly products
into an expression vector (Fig. 2b and Supplementary Fig. 4). We
used flow cytometry tests, manual colony counts and sequencing
of individual clones to measure the error rates (Supplementary
Fig. 5a,b). All three of the assays correlated well, and the error rates
determined through sequencing were 1/1,500 bp, 1/1,130 bp and
1/1,350 bp for the GFP43, GFP35 and GFP20 synthesis reactions,
respectively (Fig. 3 and Supplementary Table 2).